Induction of haemarthrosis in the TMJ of rats: Validation by MR imaging (MRI) and histology

SummaryObjectiveTo develop an animal experimental model for the induction and assessment of joint damage caused by haemarthrosis in the temporomandibular joint (TMJ) in rats.MethodsBoth TMJs of 10 young mature male Wistar rats were injected with autologous blood with additional heparin and Gd-DTPA. Two rats served as controls and were injected with physiological saline solution with additional heparin and Gd-DTPA. All rats were subsequently scanned with magnetic resonance imaging (MRI) to verify the accuracy of the intra-articular injection.The experimental rats were sacrificed after 6 and 24 h, and 2, 3 and 4 days, respectively. The rats of the control group were sacrificed after 6 and 24 h. Histopathological analysis was performed.ResultsMRI showed that all TMJs, except one were correctly injected. One injection site was considered doubtful but after renewed injection proved to be correct. Histopathological examination showed a correct injection of blood in all joints, but showed no signs of inflammation or intra-articular damage.ConclusionWe have established a reproducible animal model for the induction of haemarthrosis in the TMJ of rats. Histopathological analysis showed neither signs of intra-articular damage nor inflammation.